External endoscopic acessory control system

ABSTRACT

The present invention provides an endoscopic accessory control system that resides externally of the endoscope. The system comprises the endoscopic accessory with a working end to be placed at the distal end of the endoscope, a control sheath extending proximally external to the endoscope and a control handle joined to the proximal end of the control sheath. The control handle is slidably mounted to the exterior surface of the endoscope shaft and is configured to permit grasping of both the shaft and the handle. With the control handle and endoscope shaft grasped with one hand, the other hand of the user is left free to manipulate the endoscope distal tip controls. Additionally, the external arrangement of the control sheath leaves the working channel of the endoscope free for use of accessories or operations.

FIELD OF THE INVENTION

The present invention relates to endoscopes, accessory devices used withendoscopes and associated methods. In particular, the present inventionis directed to facilitating use of medical devices and endoscopicaccessories with an endoscope.

BACKGROUND OF THE INVENTION

Endoscopes are elongate instruments navigable through natural bodylumens and cavities of a patient for the purpose of remotely evaluatingand treating a variety of ailments. Endoscopes have viewing capabilityprovided by fiber optic elements that transmit images along their lengthto the medical care provider. Endoscopes may specifically configured inlength, diameter, flexibility and lumen configuration to navigatespecific treatment areas in the body. Examples of specificallyconfigured endoscopes are a laparoscope, duodenoscope, colonoscope,sigmoidoscope, bronchoscope and urethroscope among others. Incombination with remote viewing capability, endoscopes are frequentlyconfigured to provide a working channel through which shaft mountedtools and medical instruments may be navigated and remotely operated.Additionally, the endoscope shaft itself may carry a medical instrumentfor remotely performing a procedure at an internal treatment site, whilepermitting direct visualization of the site through the endoscope.

Presently, instruments and accessories used with endoscopes employshafts that extend from the distal working end of the instrument,proximally outside of the patient to provide a mechanism by which thephysician can manipulate the device. When used with an endoscope, theinstrument shafts are routinely passed through the working channel of anendoscope so that the device extends distally to the distal face of theendoscope while the proximal end extends out through a port in thecontrol handle of the endoscope to provide means for the physician tomanipulate the instrument. In the case of certain endoscopicaccessories, the distal end of the device attaches directly to theoutside surface of the distal end of the endoscope. However, even withaccessories that attach to the distal end of the endoscope, controlelements such as cables or wires must pass through the working channelof the endoscope.

The arrangement of instruments and accessories passing through theworking channel of the endoscope presents several problems to the useroperating the combination. First, setting up the device can becumbersome and time-consuming for the physician. In the use ofaccessories that attach to the distal end of the endoscope, thephysician or technician preparing for the procedure must first back loadcontrol elements for the accessory into the working channel of theendoscope. This procedure entails threading the control cables or wiresfor the accessory into the working channel at the distal end of theendoscope and advancing the wires through until they project from a portat the control handle of the endoscope. After inserting the controlelements through the working channel, the accessory may then be securedto the distal end of the endoscope. As a final step in the assembly, anaccessory control module that will be manipulated by the physicianduring the procedure must be connected to the proximal end of thecontrol element and then secured in some fashion to the endoscopecontrol handle. The means for connecting such a control module to theendoscope control handle may be awkward and may not be secure becausethe accessory may not be designed for the particular endoscope controlhandle set-up.

After the lengthy set-up procedure described above, another problemfaced by the physician during the procedure is controlling both theendoscope and the accessory at the same time. Typically, in anendoscopic procedure performed without an additional accessory, aphysician will hold the endoscope control handle in the left-hand whileadvancing and controlling longitudinal movement of the shaft with theright hand, grasping the shaft along its midportion. When an accessoryis added, the proximal control module presents the problem of operatinga third element that must be manipulated by the physician's hand duringthe procedure. Obviously, with only two hands available, a physicianmust have the assistance of another person to control the endoscopeaccessory combination during the procedure. Alternatively, the physicianwill have to release control of one control element in order tomanipulate the third element during various portions of the procedure.However, while the endoscope shaft or either the endoscope or accessorycontrols are released, that element will be subject to small undesiredmovements that may result in movement of the device away from theintended internal treatment site. It would be desirable to provide asystem that permits two-handed control of both the endoscope and theaccessory or instrument being used in conjunction with it.

Another disadvantage of current endoscopic accessories and instrumentsis that their control shafts must pass through a working lumen of theendoscope that could otherwise be used for other purposes during themedical procedure. In order to provide a reasonably small diameter,endoscopes can afford to provide only limited additional space forworking channels to accept accessories or provide a lumen for otheroperations. Accordingly, when the control elements for a singleaccessory take up the space provided by the working channel, the use ofother instruments or procedures through the channel are necessarilyhindered or eliminated. With control elements for the accessoryextending through the working channel, a second device, such as aninjection needle for drug therapy will not be able to pass through theworking channel and may, therefore, have to be navigated to the sitewith a second, subsequent intubation with the endoscope, which increasesprocedure time and danger to the patient. Additionally, functions suchas aspiration are hindered by the presence of control elements in theworking channel of the endoscope. With the diameter of the workingchannel being used predominantly by the indwelling control elements,vacuum through the channel is reduced and the aspirating functionimpaired. The reduced effectiveness of aspiration can be problematic inapplications where blood and tissue may cover the distal end of theendoscope inhibiting viewing capability. Insufficient aspiration may notadequately clear the area of the distal end of the endoscope of tissuedebris. Also, debris and blood that is sucked into the channel mayinterfere with the smooth operation of the accessory control elements.Additionally, procedures that require aspiration to collect areas oftissue into a chamber, such as band ligation or suturing may benegatively impacted by reduced aspiration capacity. Accordingly, itwould be desirable to provide an endoscopic accessory control systemthat does not dominate the use of the endoscope's working channel.

SUMMARY OF THE INVENTION

The present invention provides an endoscopic accessory control systemthat resides external to an endoscope with which it is used. Byremaining external to the endoscope, the control system provides aplatform by which a variety of endoscopic accessories and instrumentsmay be quickly and easily applied to any endoscope prior to a procedure.

Mounting of an accessory is facilitated by the present invention becausethe control elements for the distal operating portion of the accessoryare maintained external to the endoscope. Time need not be spent backloading control wires through the working channel of an endoscope.Rather, the distal portion may be quickly affixed to the distal end ofthe endoscope while control elements lie external to the endoscopeextending to a control handle.

The present invention improves control handle placement to facilitatetwo-handed operation because the accessory control elements do notextend through the working channel. The proximal ends of the accessorycontrol elements need not extend from the working channel proximal portat the endoscope control handle. This permits the accessory controlhandle to reside at the end of the control elements at any point alongthe endoscope shaft midportion. Thus, the control handle can be placedat a location where the physician would ordinarily grasp the endoscopeshaft to control it. The control handle for the endoscopic accessory isexternally mounted to the endoscope shaft, slidable along its length andconfigured to be grasped by a physician's hand together with the shaftof the endoscope so that both can be controlled simultaneously with thesingle hand. The ergonomic controls of the handle permit easymanipulation of the accessory control elements by the physician whilecontrolling the position of the handle along the endoscope andcontrolling movement of the endoscope shaft relative to the patient.

With the control elements for the endoscopic accessory residingexternally of the endoscope, the working channel of the endoscope isleft open for dedicated functions such as aspiration or injection or forthe passage of other instruments that may be useful in a givenprocedure.

It is an object of the present invention to provide an endoscopicaccessory control system that mounts externally to the endoscope shaftto facilitate mounting of the accessory and to avoid utilizing theworking channel of the endoscope so that it may be left open for otherinstruments or operations.

It is another object of the present invention to provide an endoscopicaccessory control system that permits two-handed operation of theendoscope and accessory, combination.

It is another object of the invention to provide an endoscopic accessorycontrol system that provides a control handle that permits grasping ofthe endoscope shaft and operation of the accessory control elements witha single hand.

It is another object of the present invention to provide an endoscopicaccessory control system that can serve as a platform by which a widevariety of instruments and operative devices can be used in conjunctionwith an endoscope.

It is another object of the invention to provide a method operating anendoscope and endoscopic accessory by using one hand to operateendoscope controls at the proximal end of the endoscope and the otherhand to operate endoscopic accessory controls positioned on theendoscope shaft between the proximal and distal ends of the shaft.

BRIEF DESCRIPTION OF THE DRAWING

The foregoing and other objects and advantages of the invention will beappreciated more fully from the following further description thereof,with reference to the accompanying diagrammatic drawings wherein:

FIG. 1 is a partial sectional illustration of the endoscopic accessorycontrol system of the present invention;

FIG. 1A is an illustration of an operator grasping an endoscope controlin the left-hand and the control handle for the system of the presentinvention in the right hand;

FIG. 1B is an illustration of an operator inserting into a patient anaccessory and sheath of the inventive system on mounted on an endoscope;

FIG. 2A is an isometric illustration of the distal portion of anaccessory and sheath prior to mounting on an endoscope;

FIG. 2B is an isometric illustration of the distal portion of anaccessory and mounted on the distal end of an endoscope;

FIG. 3 is a side view of the distal portion of an accessory bandligator;

FIG. 4 is an exploded view of the components of the distal portion of anaccessory band ligator;

FIG. 5 is a side view of the distal portion of an accessory band ligatorwith the band carrier and band driver in an extended position relativeto the static sleeve;

FIG. 6 is a side view of the distal portion of an accessory band ligatorwith the band carrier extended relative to the static sleeve and theband driver extended relative to the band carrier to discharge a band;

FIG. 7 is a sectional view of the control handle mounted on an endoscope(shown in phantom);

FIGS. 8A and 8B are isometric illustrations of left and right bodyhalves of the control handle assembly.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

The endoscopic accessory control system 10, shown in FIG. 1, comprisesan accessory distal operating portion 12 joined to a control handle 14via a control sheath 16. The distal portion 12 is removably mounted tothe distal end of an endoscope. The distal portion 12 shown in thefigures and discussed in the illustrative embodiment is a multiple bandendoscopic ligator configured to deliver ligating bands to internaltissue locations, such as at varices in order to prevent bleeding atthose sites. It should be understood that other types of accessoriessuch as forceps, cutting instruments or suturing devices could besubstituted as the operating component 12 discussed here. The distalportion of the accessory is operated by control wires slidable throughsheath 16, which extends proximally, external to the endoscope to thecontrol handle 14. The handle is slidably and removably attached to theexterior of the endoscope shaft.

In an exemplary use of the band ligator device such as treatment ofesophageal varices, the distal end of the endoscope 18 with the ligator12 attached is advanced through a patient's mouth 11 and down theesophagus as shown in FIGS. 1A and 1B. Treatment sites, varices in thisexample, are located visually with the endoscope. When a varix site islocated, the distal end of the flexible endoscope is articulated tonavigate the distal face of the scope to the varix location. Vacuum isthen applied through the endoscope to gather up a section of tissuesurrounding the varix into the ligator and an elastic ligating band isadvanced from the ligator device onto and around the gathered tissue tostop bleeding.

The distal portion 12 of the accessory device may be slidably mountedonto a distal end of an endoscope 18 as is shown in FIGS. 2A and 2B.Alternatively the distal portion may be joined to the distal of anendoscope by inserting an element of the distal portion into the workingchannel of the endoscope. The distal portion 12 is backloaded onto thedistal end 18 of the scope and slid proximally so that the distal end ofthe distal portion is substantially flush with the distal face 15 of thescope. The distal portion 12 of the device is frictionally retained onthe endoscope. When the device is mounted to an endoscope 18, the sheath16 containing control wires and connected to the distal portion, extendsparallel to the endoscope shaft, proximally to a control handle 14 asshown in FIGS. 1A and 1B.

FIG. 3 shows an assembly drawing of the distal portion 12 of anaccessory. To illustrate how the distal portion of an accessory of thepresent inventive system is configured operate and be mounted to anendoscope an example of an accessory configured as a ligating device ispresented. An exploded view of the distal portion of the devicerevealing its individual components is shown in FIG. 4. In the exampleof a band ligator shown in FIG. 3, the distal portion 12 is comprised ofthree coaxially arranged tubes: a static sleeve 20 (inner most tube); aband carrier 22 (middle tube) and; a band driver 24 (outer tube).Operation of the device involves relative sliding movement of the tubesto effect band delivery. Movement of the components of the distalportion 12 of the accessory is achieved by manipulation of controlelements on the accessory control handle 14.

When the device is navigated to a tissue treatment site such as a varixlocation, the tubes are in a retracted position, such that the banddriver 24 and band carrier 22 are positioned proximally on the staticsleeve 20. In this position the distal portion 12 does not interferewith the peripheral view through the viewing lens 11 on the distal face15 of the endoscope (FIGS. 2B and 3). When the varix site has beenreached, the band driver 24 and band carrier 22 together are sliddistally relative to static sleeve 20 to the position shown in FIG. 5.By their distal movement on the static sleeve, the band carrier 22 andband driver 24 together are extended beyond the distal face of theendoscope. The cylindrical interior of the band carrier creates a vacuumchamber, closed at its proximal end by the endoscope distal face 15 andopen at its distal end to receive tissue. Band carrier 22 and driver 24are preferably made from transparent polymer materials to minimizeinterference with peripheral viewing through the endoscope when they areadvanced beyond the distal face 15. Tissue is aspirated into the vacuumchamber when suction is applied through the vacuum port 13 on the distalface of the endoscope. With the tissue aspirated into the vacuumchamber, the band driver 24 is then slid distally relative to the bandcarrier 22. Fingers 64 projecting radially inward from the band carrierand engaging the proximal side of the distal most band serve to push aband 34 from the band carrier and onto the tissue (FIG. 6).

The exploded view of the distal portion 12 presented in FIG. 4 shows thearrangement of components that permit the operation of the accessorydescribed above. The static sleeve 20 is the innermost tube and servesas a base member for the assembly of all components that comprise thedistal portion of the device. The static sleeve has a small diameterportion 23 that steps up to a large diameter portion 21 at the proximalend of the sleeve. Fitted into the large proximal portion 21 may be anannular vacuum seal 30. A proximal retainer 28 is snap-fit into theenlarged diameter proximal portion 21, capturing the vacuum seal 30 inthe assembly. The vacuum seal helps to provide a vacuum tight frictionfit for the device onto an endoscope shaft that helps to promote greatersuction in the vacuum chamber when the band carrier is extended andvacuum applied. The sheath 16, which houses control wires that lead tothe proximally located handle, terminates and is fixed in receptacle 29of the proximal retainer 28.

Vacuum seal ring 32 is positioned between the outer surface of thestatic sleeve 20 and the interior surface of the band carrier 22. Thepresence of the vacuum seal ring between those two cylinders helps toinsure that sufficient suction is developed in the vacuum chambercreated when the band carrier 22 is slid distally relative to the staticsleeve 20 and beyond the distal face 15 of the endoscope to capturetissue.

The band carrier 22 and band driver 24 together may be movedlongitudinally relative to the static sleeve 20 by movement of thestatic control wire 52 distally relative to the sheath 16. The staticwire 52 wraps around and is held fixed in U-shaped receptacle 54 formedin rib 56 at the proximal end of the band carrier. As the control wireextends through the U-shaped receptacle, one side of the wire extendsproximally back through the sheath 16 to the control handle 14 of thedevice. The end of the control wire extending through the other side ofthe U-shaped channel continues proximally slightly to provide anextension 60 that terminates in a ball tip 58. The extension 60 slidesthrough a passage in the static sleeve and proximal retainer 28 largeenough for only the wire to pass, but not the ball tip. When the balltip reaches the passage (not shown), it stops the longitudinal travel ofthe wire in the distal direction. The remaining length of wire 60 andball tip 58 correspond in length to the amount of longitudinal travelthat the band carrier 22 can have on the static sleeve 20 withoutbecoming disconnected. Thus, the remaining portion of the wire 60 andball stop 58 comprise a safety limit stop that prevents the band carrierfrom being overextended during use.

The band driver 24 is slidably received over the band carrier withresilient arms 64 arranged to slide within diametrically opposedchannels 47 as discussed above. Band driver retainer 26 is snap-fit intothe proximal end of the band driver 24 and fixedly receives drivercontrol wire 53 so that longitudinal movement of the driver relative tothe band carrier 22 and static sleeve 20 can be affected from theproximally located handle.

As mentioned above the control sheath 16 carries slidable control wires52 and 53 each joined to control handle 14 and in particular to operatorcontrols on the control handle, as shown in FIG. 7, that permit a userto manipulate the accessory at the distal end of the sheath. Forexample, operator controls such as slide 102 and thumb lever 120 may bemounted externally on the control handle 14 and configured to move wire52 and wire 53 relative to the sheath 16 to cause corresponding relativemovement of components of the accessory distal portion 12. In theexample of a band ligator described above, movement of the wiresrelative to each other causes relative longitudinal sliding movementbetween an inner cylinder band carrier carrying ligating bands and theouter cylinder band driver configured to push bands off of the bandcarrier as shown in FIGS. 3, 5 and 6. For additional detaileddescription of how the control wires may be configured with an accessoryto accomplish an operation such as band ligation, see U.S. Pat. No.6,136,009 (Mears) or co-pending U.S. application entitled “EndoscopicBand Ligator” filed Sep. 5, 2003 based on provisional application No.60/408,555, filed Sep. 6, 2002, each of which are incorporated byreference herein.

The handle 14 is configured to be releasably and slidably mounted ontoan endoscope shaft 18 (shown in FIGS. 1A, 1B and in phantom in FIG. 7)and is sized and shaped to permit an operator to simultaneously graspand control both the handle and mid-portion of the endoscope shaft withone hand. By slightly releasing the user's grip on the handle and shaft,the handle can be slid relative to the endoscope shaft to maintain thehandle in a comfortable position relative to the user's body as theendoscope is advanced or withdrawn from the patient.

The control handle 14 may be formed from two molded plastic body halves80 and 82 shown in FIGS. 8A and 8B. The left body half 80 is shown withhandle components assembled in FIG. 7. The assembled handle is slidablyand releasably retained on an endoscope shaft 18 by the serpentinearrangement of curved forks 84, 86, 88 and 90 that extend from the bodyhalves to loosely surround the endoscope shaft. When the body halves areassembled, the forks are staggered longitudinally but curve downwardlyand around to overlap and define a circumferential pathway thereby,together, providing full circumferential support around the circularendoscope shaft residing within. Still, the forks are staggeredsufficiently to permit passage of the shaft when it is angled away fromthe longitudinal axis of the handle to slip past the fork tips. With theserpentine arrangement of the forks, the handle can be applied to orremoved from the endoscope shaft laterally, without requiring removal ofend components of the endoscope to slip the handle off the end of theshaft.

Once mounted, the handle 14 can be slid longitudinally along the scopeshaft 18 with the physician's right-hand or temporarily restrained inposition by grasping the endoscope and handle together between thecurved forks. As the handle is slid longitudinally along the endoscope,the sheath 16 freely slides through the sheath guide channel 92 formedthrough the body of the handle in order to accommodate the correspondingchange in distance between the handle and the distal portion 12 of theband ligator. To maintain smooth device operation through the sheathwhile maintaining free length adjustability, the proximal end 94 of thesheath, joined to the operator controls, is arranged to exit the handleproximal end 96. The sheath then forms a loop 99, reversing itsdirection, and reenters the handle through the sheath guide channel 92.The sheath is slidably received through sheath guide channel 92 andexits the distal end 98 of the handle and continues distally, outside ofthe endoscope, to its connection to the distal portion 12 of the bandligator.

The reverse loop configuration prevents bowing of the sheath 16 in thearea between the handle and the distal portion 12 of the device, whichcould cause interference in operating the control wires 53 and 52through the sheath as well as cause interference in the smoothlongitudinal movement of the handle along the endoscope. Instead, as thehandle moves longitudinally along the endoscope, sheath 16 slides thoughsheath guide channel 92, and the size of the loop 99 changes toaccommodate the change in distance between handle and distal portion 12.The size of the loop at the proximal side 96 of handle does notinterfere with movement of the handle along the endoscope nor does itinterfere with the operation of the control wires as the sheath is notforced to bow at the critical area of the proximal end 94, immediatelyadjacent to its attachment to the control mechanisms. A stop 101 isfixed to the exterior of the sheath to prevent it from being fed too farinto the sheath guide channel 92 such that the curvature of the loop 99becomes excessively tight, possibly impairing operation of the controlwires.

Accordingly, from the foregoing, it can be seen that an externallymounted endoscopic accessory control system adaptable to a variety ofdifferent endoscopic tools has been presented. It should be understoodhowever, that the foregoing description of the invention is intendedmerely to be illustrative thereof and that other modifications,embodiments and equivalents may be apparent to those who are skilled inthe art without departing from its spirit. Having thus described theinvention what we desire to claim and secure by letters patent is:

1. An endoscopic accessory and control system therefor comprising: anendoscopic accessory having an operating device mountable to the distalportion of an endoscope; a control handle configured to be removablymounted to the shaft of an endoscope; the control handle having aproximal end and a distal end; a control element extending from thecontrol handle to the operating device, the control handle including atleast one operator control associated with the control element by whichthe control element may be operated to control operation of theoperating device; the control handle being slidable relative to thecontrol element while remaining operatively connected to the controlelement; the control handle being constructed to enable the user tosimultaneously grip and manipulate both the endoscope shaft and thecontrol handle with a single hand; one end of the control elementextending from the proximal end of the handle and defining a proximallyextending loop, the other end of the control element extending from theloop through a guideway in the handle and out of the distal end of thehandle, the handle being slidable along the distally extending portionof the control member when the handle and accessory are mounted on theendoscope.
 2. An endoscopic accessory and control system as defined inclaim 1 wherein the control element extends externally of the endoscopeshaft when the operating device and control handle are mounted to theendoscope.
 3. An endoscopic accessory and control system as defined inclaim 1 wherein the control handle is configured to be mounted laterallyonto the endoscope shaft.
 4. An endoscopic accessory and control systemas defined in claim 3 wherein the control handle is configured to have aplurality of downwardly extending and curved forks that define acircumferential pathway through which an endoscope shaft may be slidablypassed.
 5. An endoscopic accessory and control system as defined inclaim 1 wherein the control handle is configured to enable a user tograsp directly with one hand both the handle and a portion of anendoscope shaft to which the control handle is mounted.
 6. An endoscopicaccessory and control system as defined in claim 1 wherein the controlelement includes a sheath and at least two control members extendingthrough the sheath for operating at least two functions of theendoscopic accessory operating device.
 7. An endoscopic accessory andcontrol system as defined in claim 1 further comprising, in combination,an endoscope having the operating device mounted on its distal end andthe control handle mounted to the shaft of the endoscope, the controlelement extending externally of the endoscope.